Heat dissipation apparatus incorporating a fan

ABSTRACT

A heat dissipation apparatus includes a heat sink and a fan. The heat sink includes a plurality of radial first and second fins. The first and second fins each include a main body and an extension arm extending upwardly from the main body. The main bodies and the extension arms cooperatively form a space therebetween for securely receiving the fan therein. Each extension arm defines an engaging groove communicating with the space. A height of the extension arm of each second fin is less than that of the extension arm of each first fin. A fixing recess is defined over the extension arms of the second fins. The fan includes a frame extending downwardly out a plurality of legs and radially out a fixing arm. The legs have hooks engaging in the engaging grooves, and the fixing arm is fixed in the fixing recess.

CROSS-REFERENCE TO RELATED APPLICATION

Relevant subject matter is disclosed in co-pending U.S. patent application Ser. No. 12/331,391, filed on Dec. 9, 2008, both of which are assigned to the same assignee as the present application. The disclosure of the co-pending application is incorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure generally relates to heat dissipation, and particularly to a heat dissipation apparatus utilizing a fan for enhancing a dissipating efficiency.

2. Description of Related Art

It is well known that if heat generated by electronic components, such as integrated circuit chips, during operation is not efficiently dissipated, these electronic components may suffer damage. Thus, heat dissipation apparatuses are often used to cool the electronic components.

A typical heat dissipation apparatus includes a heat sink and a fan. The heat sink is thermally connected with a heat generating electronic component. The fan is mounted on the heat sink via a plurality of screws. During operation, heat generated by the heat generating electronic component is transferred to the heat sink. The fan produces an airflow towards the heat sink to dissipate the heat therefrom.

However, in the heat dissipation apparatus, the fan is assembled to the heat sink via the plurality of screws, which complicates the assembly of the heat dissipation apparatus.

What is needed, therefore, is a heat dissipation apparatus which overcomes the above-described limitations.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present heat dissipation apparatus can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the disclosed heat dissipation apparatus. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.

FIG. 1 is an assembled, isometric view of a heat dissipation apparatus in accordance with one embodiment of the disclosure.

FIG. 2 is an exploded, isometric view of the heat dissipation apparatus of FIG

FIG. 3 is an isometric view showing a fan disassembled from the heat dissipation apparatus of FIG. 1.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, a heat dissipation apparatus in accordance with one embodiment of the disclosure is shown. The heat dissipation apparatus includes a high heat conductive base 10, a heat sink 20, a plurality of heat pipes 30 thermally connecting the base 10 with the heat sink 20, a heat conductive core 40 received in the heat sink 20, and a fan 50 mounted in a top of the heat sink 20.

The heat sink 20 is annular, and includes a pair of first fin assemblies 21 and a pair of second fin assemblies 23.

Each of the first fin assemblies 21 is sectorial, and includes a plurality of radial first fins 211 stacked along a circumferential direction of the heat sink 20. An air channel 212 is defined between every two adjacent first fins 211.

Each of the first fins 211 includes a rectangular main body 213 and an extension arm 214 extending upwardly from the main body 213. Each of the first fin assemblies 21 defines a plurality of arcuate first receiving grooves 215 therein through each main body 213, for receiving the heat pipes 30 therein, respectively. The extension arm 214 extends upwardly form an outer-upper side of the main body 213, and has a width less than that of the main body 213. The extension arm 214 forms a step 216 and defines an engaging groove 217 at an inner side thereof. A width of the extension arm 214 below the step 216 is greater than a width of the extension arm 214 above the step 216. The engaging groove 217 is wedgy, and located below the step 216. The engaging groove 217 and the step 216 are used to secure the fan 50 onto the heat sink 20. The extension arm 214 extends perpendicularly and horizontally out a top flange 218 at a top side thereof, and a step flange 219 from the step 216. All the top flanges 218 of the first fins 211 of each first fin assembly 21 cooperatively form a planar top surface 228. All the step flanges 219 of the first fins 211 of each first fin assembly 21 cooperatively form a planar step surface 229.

The second fin assemblies 23 are similar to the first fin assemblies 21, with each also being sectorial, and including a plurality of second fins 231 stacked along the circumferential direction of the heat sink 20. An air channel 232 is defined between every two adjacent second fins 231.

Each of the second fins 231 includes a main body 233 and an extension arm 234. The main body 233 of each second fin 231 is substantially triangular, such that an opening 240 is defined at an outer-lower side of each second fin assembly 23 when the second fins 231 are stacked together. Each of the second fin assemblies 23 defines an arcuate second receiving groove 235 therein through each main body 233. The second receiving groove 235 aligns with an upper one of the first receiving grooves 215, and is in communication with the opening 240.

The extension arm 234 extends upwardly form an outer-upper side of the main body 233 of each second fin 231, and has a width less than that of the main body 233. A height of the extension arm 234 of each second fin 231 is less than that of the extension arm 214 of the first fin 211. A top of the extension arm 234 is approximately level with that of the step surface 229 of the first fin assembly 21. The extension arm 234 defines a wedgy engaging groove 237 at an inner side thereof, aligning with the engaging groove 217 of the first fin 211. Alternatively, the engaging grooves 217, 237 of the heat sink 20 can be defined only in one of the first and second assemblies 21, 23, for further simplifies manufacturing procedure of the heat sink 20. The extension arm 234 extends perpendicularly out a top flange 238 at a top side thereof. All the top flanges 238 of the second fins 231 of each second fin assembly 23 cooperatively form a planar top surface 248. The top surface 248 of each second fin assembly 23 is coplanar with the step surface 229 of each first fin assembly 21. The top surface 248 of each second fin assembly 23 and the step surface 229 of each first fin assembly 21 cooperatively support the fan 50 when the fan 50 is assembled on the heat sink 20.

Each of the heat pipe 30 includes an arcuate condensation section 31. Parts of the condensation sections 31 of the heat pipes 30 are inserted into the first receiving grooves 215 of the first fin assemblies 20, and the other parts thereof are received in the second receiving grooves 235 and the openings 240 of the second fin assemblies. The heat conductive core 40 is cylindrical, and has a high heat conductivity. Preferably, the heat conductive core 40 is made of copper.

The fan 50 includes a frame 51 and an impeller 52 mounted on the frame 51. The frame 51 includes a holder 511 at a center thereof, a rim 512 at an outer periphery thereof, and a plurality of ribs 513 connecting the holder 511 with the rim 512. The holder 511 supports the impeller 52, and the impeller 52 is hung on the holder 511 and faces downwardly. The rim 512 is annular, and extends perpendicularly and downwardly out a plurality of legs 514. The legs 514 are evenly arranged on the rim 512. A hook 515 extends radially out from a free end of each leg 514. The hook 515 matches with the engaging grooves 217, 237 of the first and second fin assemblies 21, 23, for mounting the fan 50 into the heat sink 20. The rim 512 further extends radially out a pair of fixing arms 517 respectively aligning with the second fin assemblies 23. Each of the fixing arms 517 is substantially sectorial, and has an outwardly increased width along a radial direction of the heat sink 20. A height of each of the fixing arms 517 is equal to a height difference between the extension arm 234 of each second fin assembly 23 and the extension arm 214 of each first fin assembly 21. The ribs 513 are strip-shaped, for supporting the holder 511 at the center of the frame 51. Two of the ribs 513 connect with the rim 512 at locations which are adjacent to middles of the pair of the fixing arms 517, respectively, wherein one of the two ribs 513 defines a wire groove 518 therein. A wire 519 is received in the wire groove 518, and electrically connects the fan 50 with a power source, for supplying electrical power to the fan 50.

Referring also to FIG. 3, during assembly of the heat dissipation apparatus, the condensation sections 31 of the heat pipes 30 are respectively inserted into the first receiving grooves 215 of the pair of first fin assemblies 21 along two opposite orientations, with a free end of each condensation section 31 protruding out of a corresponding first fin assembly 21. The first fin assemblies 21 and the heat pipes 30 are arranged on the base 10. The first fin assemblies 21 are oriented face to face, and space from each other. The second fin assemblies 23 are inserted into spaces between the first fin assemblies 21 from top to bottom, respectively. The free end of the condensation section 31 of each heat pipe 30 has a top half entering into the second receiving groove 235 through the opening 240 of the corresponding second fin assembly 23 and a lower half received in the opening 240. At this time, the first fin assemblies 21 and the second fin assemblies 23 are alternate with each other, and cooperatively form the annular heat sink 20. All the engaging grooves 217, 237 of the first and second fin assemblies 21, 23 cooperatively form an annular engaging groove 27 of the heat sink 20. The top surfaces 248 of the second fin assemblies 23 are coplanar with the step surfaces 229 of the first fin assemblies 21. Since the height of the extension arm 234 of each second fin assembly 23 is less than that of the extension arm 214 of each first fin assembly 21, a sectorial fixing recess 25 is defined between the first fin assemblies 21 over the top surface 248 of each second fin assembly 23.

The heat conductive core 40 is enclosed by the main bodies 213, 233 of the first and second fin assemblies 21, 23, and has a circumferential periphery thereof securely soldered to inner surfaces of the first and second fin assemblies 21, 23. The first and second fins 211, 231 of the first and second fin assemblies 21, 23 extend out from the heat conductive core 40 in a radial pattern. The extension arms 214, 234 of the first and second fin assemblies 21, 23, cooperatively form a recessed space 29 over the heat conductive core 40. The steps 216 and the step surfaces 229 of the first fin assemblies 21 are located in the space 29, and the annular engaging groove 27 communicates with the space 29.

The fan 50 is aligned with and pressed into the space 29, with bottom surfaces of the rim 512 of the fan 50 abut the step surfaces 229 of the first fin assemblies 21 and the top surfaces 248 of the second fin assemblies 23. The fixing arms 517 are fixed in the fixing recesses 25, respectively, with bottom surfaces of the fixing arms 517 abutting on the top surfaces 248 of the second fin assemblies 23. At this time, the impeller 52 is just received in the space 29; top and outer side surfaces of the fixing arms 517 are coplanar with top surface and circumferential periphery of the heat sink 20, respectively; the hooks 515 of the legs 514 of the fan 50 are engaged into the engaging groove 27, for mounting the fan 50 in the heat sink 20.

During operation of the heat dissipation apparatus, the base 10 absorbs heat from the heat generating electronic component, which is transferred to the heat sink 20 via the heat conductive core 40 and the heat pipes 30. The fan 50 produces airflow toward the heat sink 20, and dissipates heat from the heat sink 20 into ambient air.

In the heat dissipation apparatus, the fan 50 is mounted in the space 29 of the heat sink 20, and the impeller 52 is enclosed by the heat sink 20, which makes the most of the cool airflow produced by the fan 50 flow through the first and second fins 211, 231. Meanwhile, the heat sink 20 enclosing the fan 50 severs as a sidewall for the fan 50, which saves material of the fan 50 and increases pressure of the airflow produced by the fan 50.

In addition, the heat sink 20 includes the steps 216 and the engaging groove 27, and the fan 50 includes the rim 512 and the legs 514 with hooks 515. Thus, additional screws are not required to stably mount the fan 50 on the heat sink 20, which simplifies structure of the heat dissipation apparatus. Furthermore, the heat sink 20 includes the fixing recesses 25, and the fan 50 includes the fixing arms 517 respectively fixed in the fixing recesses 25, which prevents the fan 50 from rotating after assembly, and is favorable to orient the fan 50 so that it can be properly assembled to the heat sink 20.

Moreover, the first and second fins 211, 231 of the first and second fin assemblies 21, 23 extend out from the heat conductive core 40 in a radial pattern. The airflow produced by the fan 50 is easily guided toward other heat generating electronic components around the heat sink 20 through the airflow channels 212, 232 between the first and second fins 211, 231. Thus, the heat dissipation apparatus not only takes heat away from the heat sink 20, but also dissipates heat from the heat generating electronic components around the heat sink 20.

It is believed that the disclosure and its advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the invention. 

1. A heat dissipation apparatus, comprising: a heat sink defining a recessed space at a center of a top end thereof, an upper portion of the heat sink surrounding the recessed space, at least one fixing recess being defined in a top end of the upper portion and at least one engaging groove being defined in an inner side of the upper portion, the at least one fixing recess and the at least one engaging groove communicating with the recessed space; and a fan comprising a frame and an impeller assembled to the frame, the frame extending downwardly out a plurality of legs and radially out at least one fixing arm, each of the legs comprising a hook at a free end thereof, the hooks of the legs engaging in the at least one engaging groove of the heat sink, and the at least one fixing arm being fixed in the at least one fixing recess, for securely mounting the fan in the recessed space of the heat sink.
 2. The heat dissipation apparatus of claim 1, wherein the heat sink comprises a pair of first fin assemblies and a pair of second fin assemblies alternate with the pair of first fin assemblies, the first and second fin assemblies cooperatively forming an annular structure, the first fin assemblies and the second fin assemblies each comprising a plurality of fins, each fin comprising a main body and an extension arm extending upwardly from the main body, the extension arms of the first and second fin assemblies cooperatively forming the upper portion of the heat sink, a height of the extension arm of each fin of the second fin assembly being less than that of the extension arm of each fin of the first fin assembly, the at least one fixing recess being defined between the pair of first fin assemblies and over the extension arms of the fins of each second fin assembly.
 3. The heat dissipation apparatus of claim 2, wherein a width of each extension arm of the first and second fin assemblies is less than that of each main body of the first and second fin assemblies, the extension arms of the first and second fin assemblies cooperatively forming the recessed space therebetween, the engaging groove being defined in at least one extension arm of the first and second fin assemblies.
 4. The heat dissipation apparatus of claim 2, further comprising at least one heat pipe with an arcuate condensation section, the first and second fin assemblies each defining at least one receiving groove therein, the second fin assemblies each further defining an opening at an outer-down side thereof in communication with the at least one receiving groove of a corresponding second fin assembly, a part of the condensation section of the at least one heat pipe being inserted into the at least one receiving groove of each first fin assembly, and another part thereof entering into the at least one receiving groove of each second fin assembly through the opening of the corresponding second fin assembly.
 5. The heat dissipation apparatus of claim 1, wherein the frame comprises an annular rim, the legs extending downwardly and the at least one fixing arm extending radially out from the rim, the heat sink forming a step above the at least one engaging groove in the recessed space, the rim sitting on the step.
 6. The heat dissipation apparatus of claim 5, wherein the heat sink comprises a pair of first fin assemblies and a pair of second fin assemblies alternate with the pair of first fin assemblies, the first fin assemblies each comprising a plurality of first fins stacked along a circumferential direction of the heat sink, the second fin assemblies each comprising a plurality of second fins stacked along the circumferential direction of the heat sink, the step being formed on each of the first fin assemblies, each of the first fins extending perpendicularly and horizontally out a step flange from the step, all the step flanges of the first fins of each first fin assembly cooperatively forming a step surface, each of the second fins extending perpendicularly and horizontally out a top flange at a top end thereof, all the top flanges of the second fins of each second fin assembly cooperatively forming a top surface, the top surface of each second fin assembly being coplanar with the step surface of each first fin assembly, the rim of the fan sitting on the top surface of each second fin assembly and the step surface of each first fin assembly, the at least one fixing arm abutting the top surface of the each second fin assembly.
 7. A heat dissipation apparatus, comprising: a heat sink comprising a plurality of radial fins, each of the fins comprising a main body and an extension arm extending upwardly from the main body, a width of each extension arm of the fins being less than that of each main body of the fins, the main bodies and the extension arms of the fins cooperatively forming a space therebetween, the extension arms of the fins defining at least one engaging groove communicating with the space, the extension arms of a part of the fins protruding upwardly out from the extension arms of the other part of the fins, such that at least one fixing recess being defined at a top end of the heat sink; and a fan comprising a frame and an impeller assembled to the frame, the frame extending downwardly out a plurality of legs and radially out at least one fixing arm, each of the legs comprising a hook at a free end thereof, the hooks of the legs engaging in the at least one engaging groove of the heat sink, and the at least one fixing arm being fixed in the at least one fixing recess, for securely mounting the fan in the space of the heat sink.
 8. The heat dissipation apparatus of claim 7, wherein the fins comprise a plurality of first fins and a plurality of second fins, the first fins being stacked together to cooperatively form a pair of first fin assemblies, the second fins being stacked together to cooperatively form a pair of second fin assemblies, the first fin assemblies being alternate with the second fin assemblies to form an annular structure, the extension arms of the first fins of the first fin assemblies protruding upwardly beyond the extension arms of the second fins the second fin assemblies.
 9. The heat dissipation apparatus of claim 8, wherein the frame comprises an annular rim, the legs extending downwardly and the at least one fixing arm extending radially out from the rim, each extension arm of the first fins of the first fin assemblies forming a step above the at least one engaging groove in the space, the rim sitting on the steps of the first fin assemblies.
 10. The heat dissipation apparatus of claim 9, wherein each of the first fins extending perpendicularly out a step flange from the step, all the step flanges of the first fins of each first fin assembly cooperatively forming a step surface, each of the second fins extending perpendicularly and horizontally out a top flange at a top end thereof, all the top flanges of the second fins of each second fin assembly cooperatively forming a top surface, the top surface of each second fin assembly being coplanar with the step surface of each first fin assembly, the rim of the fan sitting on the top surface of each second fin assembly and the step surface of each first fin assembly, the at least one fixing arm abutting the top surface of the each second fin assembly.
 11. The heat dissipation apparatus of claim 8, further comprising at least one heat pipe with an arcuate condensation section, the first and second fin assemblies each defining at least one receiving groove therein, the second fin assemblies each further defining an opening at an outer-down side thereof in communication with the at least one receiving groove of the corresponding second fin assembly, a part of the condensation section of the at least one heat pipe being inserted into the at least one receiving groove of each first fin assembly, and another part thereof entering into the at least one receiving groove of each second fin assembly through the opening of the corresponding second fin assembly. 